I replaced my iPhone 5s charger cable but now it won't charge.

To be more specific, it sometimes does charge inexplicably, but it takes around 20 minutes just to get 4% more charge, then it loses charge for no reason! When it does charge, it doesn't show the lightning bolt! I got the charger cable and it said it worked on both iPhone 5 and iPhone 6, it didn't say anything about iPhone 5s but I just ignored that fact because it's almost the same thing as an iPhone 5. I don't know if that's the problem, but nevertheless I need help now! This is getting ridiculous and I've only had the new cable for about 3 days!